Alert archive / Iowa / Tornado Warnings in 2002

Tornado Warning 4, NWS Quad Cities, IA

April 18, 2002Jones County, Linn County, Iowa

NWS Quad Cities, IA issued this tornado warning at Apr 18, 2002, 8:35 PM CDT for Jones County, Linn County, Iowa. It was in force for 35 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Apr 18, 2002, 8:35 PM CDT (01:35 UTC)
Expired: Apr 18, 2002, 9:10 PM CDT
In force: 35 min
Issued by: NWS Quad Cities, IA
Area: Counties, with a storm outline in the text

Counties Jones County, IA, Linn County, IA

The radar

The Quad Cities radar (KDVN), 85 km from the middle of the area, began a volume at 01:38 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Apr 18, 9:20 PM CDT	Hail 1	Wyoming, IA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Apr 18, 8:30 PM CDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 1.6 hours before the alert went out and 89 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1636 J/kg
Mixed-layer CIN: -24 J/kg
Mixed-layer LCL: 1702 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 113 m²/s²
0-3 km storm-relative helicity: 200 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WFUS53 KDVN 190135
TORMLI
IAC105-113-190210-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
833 PM CDT THU APR 18 2002

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  JONES COUNTY IN EAST CENTRAL IOWA
  EASTERN LINN COUNTY IN EAST CENTRAL IOWA

* UNTIL 910 PM CDT

* AT 830 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM WITH A POSSIBLE TORNADO OVER ALBURNETT...OR 12
  MILES NORTH OF CEDAR RAPIDS...MOVING EAST AT 60 MPH.

* THE TORNADO IS EXPECTED TO BE NEAR...
   WHITTIER BY 835 PM CDT.
   FAIRVIEW BY 840 PM CDT.
   HALE BY 850 PM CDT.
   OXFORD JUNCTION BY 855 PM CDT.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT OR ON THE
LOWEST FLOOR OF A BUILDING IN AN INTERIOR HALLWAY OR ROOM.

LAT...LON 4224 9159 4207 9166 4196 9092 4212 9091

REA

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 18, 7:51 PM CDT	Severe Thunderstorm Warning	DVN	Benton	34 min
Apr 18, 7:55 PM CDT	Tornado Warning	DVN	Benton	35 min
Apr 18, 8:09 PM CDT	Tornado Warning	DVN	Buchanan	36 min
Apr 18, 8:17 PM CDT	Severe Thunderstorm Warning	DVN	Linn	33 min
Apr 18, 8:27 PM CDT	Tornado Warning	DVN	Iowa	48 min
Apr 18, 8:44 PM CDT	Severe Thunderstorm Warning	DVN	Dubuque	31 min
Apr 18, 8:59 PM CDT	Tornado Warning	DVN	Johnson	46 min
Apr 18, 9:16 PM CDT	Severe Thunderstorm Warning	DVN	Jackson	44 min
Apr 18, 9:28 PM CDT	Tornado Warning	DVN	Cedar	32 min
Apr 18, 9:30 PM CDT	Severe Thunderstorm Warning	DVN	Clinton, Jones	45 min
Apr 18, 9:50 PM CDT	Severe Thunderstorm Warning	DVN	Scott	40 min
Apr 18, 9:59 PM CDT	Severe Thunderstorm Warning	DVN	Jackson	51 min

Nearby

Tornado Warnings in Iowa, 2002 Every tornado warning in 2002 Tornadoes in 2002

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.